This invention relates to an assembly and method for installing a pipe liner within a sewer pipe, and specifically to an assembly and method for installing a pipe liner within a specific discrete section of a sewer pipe.
Typically, a sewer pipe includes a main line, which extends substantially parallel to a street or road. Residents or buildings include branch lines that extend from the building to the main line. Conventional repair of sewer pipes includes digging the pipes up and replacing the damaged areas. Often times it is undesirable to dig a hole to obtain access to the sewer pipes. Further, digging a hole to gain access to sewer pipes is expensive, unsightly, and very undesirable along with being time consuming.
It is known in the art to reline sewer pipes in place through access holes such as manholes. The relining in place process includes a resin impregnable liner installed within the tube and held in place until hardened. The resin impregnable liner becomes a new pipe installed within the old pipe. This method of repair is essentially transparent to residents, meaning that the surrounding area is not disturbed or dug up. The relining process includes the use of an inflatable bladder along with the resin impregnable pipe liner that inserts within the sewer pipe. The bladder tube inflates to drive the resin impregnable pipe liner outward against the inner surface of the sewer pipe. The bladder tube remains inflated in place until the resin impregnable pipe liner hardens.
Typically, main line sewer pipe are relined by securing one end of the pipe liner and bladder at a first manhole and driving the bladder tube to a second manhole. Such a process necessarily will block any branch or lateral sewer lines feeding into the main line. These branch lines are later reinstated by various types of cutting machines either inserted within an opposite end of the branch line or from the main line. Often the opposite end of the branch line is accessible only from within a residence. As appreciated, dragging equipment into a private residence for reinstating the connection of a branch sewer line to a main sewer line is often not desirable.
Further, reinstatement of the branch line from within a main line requires knowledge of the precise location of the branch line and the ability to locate appropriate cutting machines at that location. This may require expensive and cumbersome equipment. It is for these reasons that methods of relining only those sections requiring repair have been developed.
Conventional methods of relining only discrete locations within a main line sewer pipe include the use of a combined bladder/pipe liner assembly having a pipe liner attached to the bladder by way of a frangible connection. This method operates by inflating the bladder assembly into the main line sewer with the pipe liner attached thereto. Once the pipe liner has hardened the bladder is tugged ripping the frangible connection to allow the removal of the bladder tube. This method requires a custom fabricated bladder/tube assembly that increases cost and involves a substantial lead-time. As appreciated, lead-time increases costs associated with a pipe relining operation. Further, often a contractor is responsible for relining a great many sewer pipes of differing lengths and diameters. The effort of accounting for each custom fabricated bladder/pipe liner assembly adds additional expense and burden.
Accordingly, it is desirable to develop an assembly and method for installing within a resin impregnable pipe liner within a discrete sections of main line sewer pipe without necessitating reinstatement of each branch line pipe or the need for custom fabricated bladder and pipe liner assemblies.
An embodiment of this invention is a launcher assembly including an inflatable member actuatable between inflated and deflated conditions for anchoring the launcher at a desired location within a sewer pipe during installation of a pipe liner to discrete locations within a main line sewer.
The launcher includes a body defining a passage through which the pipe liner and a bladder assembly pass during installation into a sewer pipe. Preferably the body is cylindrical having with an inner diameter defining the passageway and an outer diameter. An inflatable member mounts to an outer diameter of the body.
The inflatable member attaches to the body to define a cavity. The body includes a mounting slot that cooperates with a pin disposed on collar. A clamp secures a carrier tube to the collar. The carrier tube is a flexible tube extending within the main line providing a protected passage for the pipe liner and bladder assembly. The carrier tube attaches to the collar by way of the clamp. An o-ring is disposed between the body of the launcher and the collar of the carrier tube to create an airtight seal.
In preparation of installation within the sewer pipe the pipe liner and bladder tube are cuffed over the inflatable member such that upon inflation of the inflatable member both the bladder tube and pipe liner are trapped between the body of the launcher and an inner surface of the sewer pipe. The remaining length of the pipe liner and bladder tube are disposed within the passage defined by the body of the launcher assembly. Once the inflatable collar has trapped the bladder and pipe liner against the inner surface of the sewer pipe, air pressure applied, as indicated by arrows A, drives the bladder assembly and pipe liner into the main line sewer pipe. As the air pressure indicated at A, drives the bladder and pipe liner into the sewer pipe, the entire length of the pipe liner is drawn through the passage of the launcher assembly. The bladder remains inflated until the pipe liner hardens. Once the pipe liner is hardened, the bladder is deflated and the launcher removed from the sewer pipe.
Another embodiment of the launcher assembly includes a guide and a retainer. The retainer along with the inflatable member define an outer diameter sized to correspond to the inner diameter of the sewer pipe in which a pipe liner is be installed. The guide includes a smaller diameter, allowing for attachment of a positioning device to an attachments lug. Further the outer diameter of the guide defines a passageway through which the pipe liner and bladder assembly pass. The guide and the retainer can be constructed as a single assembly.
Another embodiment of the launcher includes a retainer detachably assembled to the guide. The retainer includes an outer diameter specifically sized for application of a pipe liner to a sewer line of a specific inner diameter or range of diameters. As appreciated, for sewer pipes of differing inner diameters different retainer outer diameters are required, while a single outer diameter of the guide can be used for a greater range of sewer pipe applications. The guide provides a passage through which the pipe liner and bladder tube assembly pass during installation. The passage size allows non-restrictive movement of the pipe liner and bladder assembly therethrough during installation and therefore can be of a smaller diameter relative to the retainer and the inner diameter of the sewer pipe.
The guide includes a flange with a plurality of openings for fasteners. A seal disposed between the guide and the retainer prevents air leakage during assembly. Because the guide is separate and attachable to the retainer, retainers of differing sizes can be mated to a single guide. This reduces the amount of equipment required for assembly of pipe liners to sewer pipes of differing sizes.
This invention also includes a method for installing a pipe liner within a sewer pipe. The method of this invention provides for the installation of a pipe liner to a discreet portion of a sewer pipe by anchoring the pipe liner and bladder assembly with the launcher assembly and driving the pipe liner and bladder tube assembly forward of the launcher assembly to line the desired section of sewer pipe.
The method includes the installation of the pipe liner and bladder assembly to the body of the launcher. Preparation for installation of the pipe liner into the sewer pipe includes installing the bladder tube into the launcher assembly. Installation of the bladder tube includes cuffing or overlapping the bladder assembly around the inflatable member. The bladder tube assembly is then clamped to the outer surface of the body by way of hose clamp.
In the next step, the pipe liner is cuffed over the inflatable member on the outside of the bladder. The pipe liner is impregnated with a curable resin before being installed onto the launcher assembly. A positioning device attaches to lugs of the launcher assembly and moves the launcher into position. Cameras are positioned in multiple locations within the sewer line to provide necessary views for proper positioning of the launcher. The launcher is positioned relative to a discrete location within the sewer pipe such as a hole or damaged section of sewer pipe. Further, the launcher may also be position such that pipe liner is not installed over openings leading to branch sewer lines.
The inflatable collar is then actuated to the inflated condition to trap the bladder and pipe liner against the inner surface of the sewer pipe. Air pressure applied to the bladder tube assembly drives the bladder assembly and pipe liner into the main line sewer pipe. Extension of the bladder assembly and pipe liner occurs substantially instantaneously at a pressure creating enough force to drive the pipe liner into the sewer pipe. The inflatable member is then deflated. The bladder supports the launcher assembly once fully inflated and remains inflated until the pipe liner hardens. Once the pipe liner is hardened, the bladder is deflated and the launcher removed from the sewer pipe.
The launcher assembly of this invention provides a device and method of anchoring a pipe liner and bladder assembly within a main line sewer pipe allowing installation of the pipe liner to a specific discrete location within the main line sewer pipe.